When you invest in love, it is like investing in equities or derivatives: you never have a guarantee on return. Not even on repayment. There’s no one who could underwrite you to get your money back.
So why are you afraid of being deceived?
The worst thing that could happen to you is to be disappointed. You would lose your illusions. You would lose something that doesn’t belong to you anyway. It’s only an illusion, not your values, nothing you could truly worship.
Basically, such a realization would be something positive. Even if it is difficult so see it like this once you have trusted. But I’m sure that an illusion you will never be able to catch is even worse than being disappointed once and being able to start something new.